Camera capable of correcting blurring

ABSTRACT

A camera capable of blurring correction includes an acceleration sensor detecting camera-shake amount, and a blurring correcting device correcting blurring of image on the basis of the sensor output. When a lens of the camera is driven for automatic focusing, the blurring is not corrected using an output of the acceleration sensor. Accordingly, blurring is not wrongly corrected.

This application is a continuation of application Ser. No. 07/618,961,filed Nov. 28, 1990, now abandoned.

This application is a divisional of application Ser. No. 08/439,183,filed May 11, 1995, now U.S. Pat. No. Re 35,583, which is a reissue ofapplication Ser. No. 07/758,309, filed Aug. 28, 1991 (now U.S. Pat. No.5,210,563, which was surrendered on Sep. 6, 1996 ), which is acontinuation of application Ser. No. 07/618,961, filed Nov. 28, 1990,now abandoned.

BACKGROUND OF THE INVENTION Field of the Invention

The present invention relates to cameras capable of correcting blurringoccurring due to camera movement or camera-shake (hereinafter referredto as blurring), and particularly to cameras capable of blurringcorrection which can perform automatic focusing control (hereinafterreferred to as AF).

Description of the Related Art

Cameras capable of correcting blurring have been proposed recently. As acamera-shake sensor in a camera capable of blurring correction, onewhich employs an angular velocity sensor is possible. The blurringcorrection is performed by detecting camera-shake amount of a cameraemploying an angular velocity sensor and driving a lens to correct it.

Recent cameras have an AF function. In a camera having an AF function, alens is automatically driven for focusing on an object. Then,acceleration noise is produced in the camera-shake detecting sensor dueto vibration of the motor and vibration of the driving mechanism. It wasthen recognized that the blur is not properly corrected because correctangular velocity outputs cannot be obtained accordingly.

Furthermore, in a camera capable of blurring correction, the blurringamount of image of an object to be photographed on film is corrected inexposure of the film. In order to correct the blurring amount of theobject on the film, a blurring amount correcting lens provided in agroup of lenses is driven at a speed necessary for correction.

In a camera capable of hand-shake correction, the hand-shake iscorrected as described above. As compared to the performance of theblurring correcting means, however, the speed required for correction ofa correcting lens for hand-shake correction is sometimes too fast forcorrection, or sometimes the amount to be corrected is so large that thecorrection is made insufficiently. In these cases, even with a camerahaving correcting means, there is a problem that the hand-shake cannotbe sufficiently corrected, so that blurring exists in a picture.

In addition, cameras capable of flashlight emission and blurringcorrection have been proposed recently. Only one power source placegenerally exists in a camera, so that boosting for flash and driving ofblurring detecting sensors are generally performed using a single powersource in a camera capable of flashlight emission and blurringcorrection.

When a flash circuit is boosted by a power source, the voltage of abattery is likely to fluctuate, so that a problem might occur that thedata provided by a shake detecting sensor such as an angular velocitysensor is not correct due to the influence.

SUMMARY OF THE INVENTION

Accordingly, it is an object of the present invention to performblurring correction correctly in a camera capable of detection ofcamera-shake.

It is another object of the present invention to perform blurringcorrection as much as possible in a camera capable of detection ofcamera-shake.

The above objects of the present invention are attained by a cameracapable of camera-shake detection including the following elements. Thatis, a camera according to the present invention includes a camera-shakeamount detecting sensor for detecting a camera-shake amount of saidcamera, a blurring corrector for correcting blurring of said camera onthe basis of said camera-shake amount, a focus adjusting optical systemfor focusing on an object image, a driver for driving the opticalsystem, and a controller for controlling the driver and the blurringcorrector so that the blurring corrector does not use outputs of thecamera-shake detecting sensor when the optical system is being driven.

In the period in which vibration noises are produced because the opticalsystem is driven, the blurring correcting device does not use outputs ofthe camera-shake detecting sensor. Accordingly, wrong detection ofblurring amounts is avoided. As a result, in a camera capable ofcamera-shake detection, correct blurring correction is possible.

Preferably, a camera according to the present invention includes anexposure amount controller for controlling exposure to film, acamera-shake detecting sensor for detecting said camera-shake amount, ablurring corrector for correcting image blurring caused by thecamera-shake in response to an output of the camera-shake detectingsensor, a determining device for determining whether the camera-shakecan be properly corrected or not, an auxiliary light means for lightingthe object, and a controller for making the auxiliary lightening deviceemit light when the determining device determines that the camera-shakecannot be properly corrected in the exposure.

Generally, a blurring amount is expressed as a product of exposure timeand blurring velocity. When the above-identified exposure time orblurring velocity exceeds a correctable amount, the determination devicedetermines that blurring correction is impossible. In this case, theblurring amount can be reduced by reducing the exposure time. If theexposure time is reduced at that time, however, the exposure amountdecreases. Therefore, in the present invention, flashlight is emitted tocompensate for the insufficient exposure amount due to the decrease inexposure time.

The foregoing and other objects, features, aspects and advantages of thepresent invention will become more apparent from the following detaileddescription of the present invention when taken in conjunction with theaccompanying drawings.

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a perspective view of a camera to which the present inventionis applied.

FIG. 2 is a block circuit diagram of the camera shown in FIG. 1.

FIGS. 3-6 and 10 are flow charts showing operation of the cameraaccording to the present invention.

FIG. 7 is a diagram showing an optical system of a camera according tothe present invention.

FIG. 8 is a flow chart showing main portions of the method of correctingblurring according to the present invention.

FIGS. 9A-9C are diagrams showing relationship between a blurringvelocity of an image on a film surface and an exposure time.

FIGS. 11A-13 are flow charts showing operation of the camera in the casewhere the blurring correction tracking according to the presentinvention is impossible.

FIGS. 14A and 14B are diagrams for describing the effect in the casewhere the blurring correcting is impossible.

DESCRIPTION OF THE PREFERRED EMBODIMENTS

FIG. 1 is a perspective view conceptually showing the structure of acamera as one embodiment of the present invention. In a camera body 11,angular velocity sensors Sx and Sy for detecting angular velocities in alongitudinal shake direction and a lateral shake direction,respectively, are provided in a plane (the x-y plane in the figure)vertical to an optical axis (the z axis in the figure) of a taking lens12.

FIG. 2 is a block circuit diagram showing portions related to control ofthe camera shown in FIG. 1. Referring to FIG. 2, the camera according tothe present invention includes a microcomputer μC administratingsequence control of the entire camera, exposure calculation and exposurecontrol. To the microcomputer μC, peripheral circuits CT₁ and CT₂ whichwill be described in detail later, some switches for controllingoperation of the camera, and a power source for supplying power to themicrocomputer and the peripheral circuits CT₁ and CT₂ are connected.

Peripheral circuit CT₁ includes a light measuring circuit LM formeasuring brightness of an object, converting the same into a digitalsignal and transmitting the same to the microcomputer μC, a distancemeasuring circuit MD for converting an analogue signal indicating thedistance supplied from a distance detecting circuit into a digitalsignal and supplying the same to the microcomputer μC, a lens drivingcircuit LD for driving a lens for focus adjustment on the basis of thedistance obtained according to the data of the distance measuringcircuit MD, an exposure control circuit AE having a shutter also usedfor an aperture for controlling the shutter on the basis of the shutterspeed determined on the basis of output of the light measuring circuitLM and also automatically controlling the aperture, and a filmsensitivity reading circuit ISO for reading film sensitivity Sv recordedon a film chamber and transmitting the same to the microcomputer μC.

Peripheral circuit CT₂ includes angular velocity sensors Sx and Sy fordetecting angular velocities in a longitudinal shake direction and alateral shake direction of the camera and transmitting the camera-shakeamount to the microcomputer μC, and a blurring correcting lens controlcircuit Cxy for driving a lens LC in a plane vertical to the opticalaxis for correcting blurring which is caused by the camera shake. Theshake of the camera is corrected by the blurring correcting lens controlcircuit Cxy supplying as an output a correction signal to the correctinglens driving circuits Cx and Cy.

The microcomputer μC further includes a display circuit DISP for warningblurring, a zoom encoder ZEN for transmitting a focal length of takinglens 12 which is a zoom lens to the micro computer μC, a flash circuitFL for emitting a flash light and an aperture encoder AVEN fortransmitting an aperture value to the microcomputer μC.

Next, switches will be described. Switches connected to themicrocomputer μC include a main switch SM which has an ON state fordriving a camera and an OFF state for keeping a camera standing still, apreparatory switch S1 which is turned on upon a first stroke of arelease button (not shown), a release switch S2 which is turned on upona second stroke of the release button, and an exposure starting switchSST which is turned on when the shutter starts operating to startexposure. When preparatory switch S1 is turned on, preparatory operationsuch as the light measuring operation, distance measuring are performed.When the release switch S2 is turned on, exposure control is performed.

next, portions related to a power source will be described. A directoutput voltage Vo of power source battery E is supplied to peripheralcircuits CT₁ and CT₂ through a flash circuit FL and first and secondfeeding transistors Tr1 and Tr2, respectively. A capacitor C1 forback-up is charged by the power source battery E through a diode D1 forreverse current prevention. A charging voltage V_(DD) of capacitor C1for back-up is supplied to the microcomputer μC, the display circuitDISP and the zoom encoder ZEN, the aperture encoder AVEN. Theabove-described peripheral circuits CT₁, CT₂ include circuits of largepower consumption, so that the voltage of power source battery E maytemporarily decrease when it is being driven. Even in the voltagedecrease time, the microcomputer μC is supplied with power fromcapacitor C1 for back-up, so that it operates properly.

Now, the description about a hardware configuration of the embodiment iscompleted. Next, the soft wear configuration of the present embodimentwill be described.

FIG. 3 is a flow chart showing contents of an interruption SMINT carriedout when the main switch SM is operated to be switched from OFF to ON orfrom ON to OFF. If this interruption SMINT is produced, it is determinedfirst as to whether the main switch SM is ON or not (#5). If the mainswitch SM is OFF, it is determined that the main switch SM is operatedfrom ON to OFF. As a result, boosting of flash circuit FL is stopped,the first feeding transistor Tr1 is turned off, and power supply to thefirst peripheral circuit CT₁ including light measuring circuit LM and soforth is stopped. Next, the second feeding transistor Tr2 is turned off,and power supplying to the second peripheral circuit CT₂ includingangular velocity sensors Sx and Sy is stopped. The display is eliminatedand the microcomputer μC attains a half state (#65-#75). If the mainswitch SM is ON in step #5, all the flags are reset and boosting of theflash circuit is started to start charging a capacitor (not shown) offlash circuit FL. Next, the feeding transistor Tr2 is turned on to startsupplying power to the second peripheral circuit CT₂ including angularvelocity sensors Sx and Sy, and a timer T₁ is reset and started(#10-#20). The timer T₁ is a holding timer for holding power supplyingto peripheral circuits CT₁ and CT₂. Next, a determination is made as towhether preparatory switch S1 is ON or not in the step #25, and if it isON, the subroutine of S1 ON is carried out in step #30 and the programreturns to step #25.

FIG. 4 is a flow chart showing the subroutine of the above-described S1ON. When the preparatory switch S1 is turned on, boosting of flashcircuit FL is stopped (#100). Switch S1 is turned off and adetermination is made as to whether a flag S1 OFF F indicating that ahold time (10s) has passed is set or not (#105), and if it is set, it isreset, transistor Tr2 is turned on, and power supply holding timer T₁ isreset-started and the program advances to step #125 (#110-#120).

If the flag S1 OFF F is not set in step #105, the program immediatelyadvances to step #125, transistor Tr1 is turned on to supply power toperipheral circuit CT₁ and light measuring data and distance measuringdata are inputted (#125-#135).

Next, referring to FIG. 5, a subroutine of the light measuring shown instep #130 of FIG. 4 will be described. A brightness value Bv is readfrom light measuring circuit LM, and the film sensitivity Sv is readfrom film sensitivity reading circuit ISO. An exposure time T_(EV) isfound from the exposure value Ev obtained as exposure value Ev=Bv+Sv,and the program returns (#205-#220).

Referring to FIG. 4 again, next, a focal length F is read from zoomencoder ZEN (#140), a flag FLF indicating flash light emission is reset(#150), and it is detected whether a flash circuit FL has been chargedor not (#160). If charging of the flash circuit FL is not completed(when the potential of a terminal CHC shown in FIG. 2 is H, “H”corresponds to high level whereas “L” corresponds to low levelhereinafter), the program advances to step #165, and boosting of flashcircuit FL is started. Specifically, the potential of a terminal STA ismade H (#165). Next, if warning of blurring is made in step #170, awarning display of camera-shake is eliminated and the program returns tostep #160 (#170, #175). Here, the warning display is eliminated whenflash circuit FL is boosted because the blurring amount is notcalculated in boosting in which the voltage of the battery is verylikely to fluctuate and the data indicating the blur amount is notprecise. When charging of flash circuit FL is completed in step #160(when the potential of a terminal CHC is L), boosting of flash circuitFL is stopped (the potential of the terminal FTA is made L) and adetermination is made as to whether release switch S2 is turned on ornot (#180, #185). If release switch S2 is ON, exposure is controlled,and the program returns (#185, #190). If switch S2 is not ON in step#185, a determination is made as to whether switch S1 is ON or not, andif switch S1 is OFF, the program returns (#195). When switch S1 is ON instep #195, the blurring amount is calculated and displayed, and programreturns to step #160 (#195-#205).

Referring to FIG. 6, a subroutine of blurring amount calculation shownin step #200 of FIG. 4 will be described. First, angular velocities(shake data) ΔVx and ΔVy are supplied from angular velocity sensors Sxand Sy, respectively (#250). Assuming that the preceding angularvelocity Bx is LBx, finding an angular velocity ΔBx in the x directionon the image surface according to the focal length f, a flag BLx flagindicating that the angular velocity (blurring amount) in the xdirection is large is reset (#255-#265).

The angular velocity (blurring data) is found according to the focallength because the blurring amount changes with the focal length, whichincreases as the focal length increases.

Next, details of the blur amount calculation will be described. Anangular velocity obtained from outputs from angular velocity sensors Sxand Sy (wherein the electric charge amount is converted into a voltage)is regarded as θ. Here, the camera-shake amount B detected by theangular velocity sensors Sx and Sy can be expressed as follows,

B={dot over (θ)}

A blurring amount Δu in a surface equivalent to that of a film is afunction of focal length f of a taking lens 12 at that time and afunction of tangent of the blur angular θ. Accordingly,

Δu=ƒ·tanθ  (1)

Also, Δu=ƒ·tan (f{dot over (θ)}dt).  (2)

Here, when an image velocity on film is FB, then $\begin{matrix}{{FB} = {\frac{u}{t} = {\frac{}{t}\left\{ {{f \cdot \tan}\quad \left( {f\quad \overset{.}{\theta}\quad {t}} \right)} \right\}}}} & (3)\end{matrix}$

The speed UB for moving a correcting lens for blurring correction has aconstant relationship with blurring velocity, u, and then if a constantis a, the following expression holds. $\begin{matrix}{{FB} = {\frac{u}{t} = {{a\frac{u}{t}} = {a \cdot f \cdot \frac{{\tan \left( {f\quad \overset{.}{\theta}\quad {t}} \right)}}{t}}}}} & (4)\end{matrix}$

This Du/dt has a limitation for movement, which is expressed as UB_(K).Then, the speed UBx at which the correcting lens is to be movedcalculated from the obtained angular velocity can be expressed asfollows, $\begin{matrix}{{Ubx} = {\frac{{Ux}}{t} = {a \cdot f \cdot \frac{{\tan \left( {f\overset{.}{\quad \theta}\quad {t}} \right)}}{x}}}} & (5)\end{matrix}$

In the expression, an index x indicates a value about the x direction.In step #285 of FIG. 6, determination is made as to whether the obtainedspeed Ubx at which a correcting lens is to be moved for blurringcorrection is within UB_(K) which is a movable limitation speed or not,in other words, whether the obtained speed to be corrected is within acorrectable range or not.

The speed UB at which a correcting lens is to be moved is, UB=a·FB andthe following relationships hold,

Ubx=α·FBx

UBy=α·FBy

UBK=α·FBK

That is, the determination in step #285 means the same as thedetermination about whether |Fbx|≧FB_(K) or not.

Since a blurring amount can be obtained by a product of blurring speedand blurring. It is assumed that exposure time T_(EV) is generallynecessary for photographing. In view of this, time usable for correctionT_(K) is examined. The time usable for correction T_(K) is found out onthe basis that the correcting lens is moved at the correctable maximumspeed UB_(K) in one direction.

Returning to step #285 of FIG. 6, when it is determined that the speedUbx at which a correcting lens is to be moved in an x direction is acorrectable speed UB_(K) or more, the program advances to step #290,where it is determined whether the exposure time T_(EV) is longer thanthe time usable for correction T_(K) or not.

Next, a description will be given to the uncorrectable blurring amountBlx. For the correcting lens limitation speed UB_(K) and the speed atwhich it is to be moved Ubx, the blurring speed on the film surface isexpressed as FB_(K) and Fbx. In this case, if exposure time T_(EV)≧timeusable for correction T_(K), uncorrectable blurring amountBlx=(|Fbx|−FB_(K))·T_(K)+|Ubx|·(T_(EV)−T_(K)), and,

T_(EV)<T_(K), then,

Blx=(|Fbx|−FB_(K))·T_(EV)

then, the program advances to step #330.

FIG. 7 is a diagram showing a lens optical system of a camera withblurring correction according to the present invention. Referring toFIG. 7, the optical system according to the present invention will bedescribed. The optical system of a camera with blurring correctingaccording to the present invention includes an AF lens AFL driven by anAF motor for focusing, and a group of lenses including a correcting lensLC moving vertically to an optical axis for blurring correction. With anoutput B of an angular velocity sensor Sx (only x direction isconsidered here), the correcting lens LC is moved at a speed of UB inthe direction designated by the arrow in the figure. When the correctinglens LC is moved at a speed UB in the direction designated by the arrowin the figure, the image on the surface of the film FP moves at a speedof FB. The motor for AF is located in the vicinity of the camera body 11where an angular velocity sensor Sx is located rather than in thevicinity of the lens optical system.

FIG. 8 is a flow chart schematically showing the method of blurringcorrection according to the present invention. First, a blurring amountis calculated (#900), and a moving velocity Ubx to be corrected by thecorrecting lens shown in FIG. 7, exposure time T_(EV) and time usablefor correction T_(K) are calculated (#905). Next, on the basis of theabove-described calculated results, it is determined whether thecorrecting lens LC is a lens movable at a speed necessary for correctionor not (#910). Specifically, a determination is made as to whether thespeed UB at which the correcting lens is to be moved is smaller than thelimitation speed UB_(K) of the correcting lens. If a determination ismade in step #910 that the speed Ubx at which the correcting lens LC isto be moved is smaller than the limitation speed UB_(K), the programgoes to step #915, and it is determined whether the exposure time T_(EV)exceeds the permittable exposure time T_(K) or not (#915). If it isdetermined that the exposure time T_(EV) does not exceed the exposurepermittable time T_(K) in step #915, tracking for blurring correction ispossible since there is no problem in connection to the moving speed forcorrection of correcting lens LC and exposure time (#925). On the otherhand, if the exposure time T_(EV) exceeds the permittable exposure timeT_(K) in step #915, tracking for blurring correction is impossiblebecause of a problem concerning exposure time. The case corresponds tothe case III described later concerning FIG. 9C.

In the case where the speed Ubx at which the correcting lens LC movesexceeds the limitation speed UB_(K) of the correcting lens in step #910,a determination is made as to whether the exposure time T_(EV) exceedsthe permittable exposure time T_(K) or not as well as in step #915(#920). If it is determined that the exposure time T_(EV) exceeds thepermittable exposure time T_(K) in step #920, it corresponds to the caseII described concerning FIG. 9B, and if the exposure time T_(EV) doesnot exceed the permittable exposure time T_(K), it corresponds to thecase I described concerning FIG. 9A. Anyway, in these cases, blurringcorrection tracking is impossible (#930).

Next, the cases where blurring correction tracking expressed in the caseI-case III described above is impossible will be described.

FIGS. 9A-9C are diagrams for showing blurring correction trackingimpossible regions in the case corresponding to the cases I-III in whichblurring correction tracking is impossible described in step #830 ofFIG. 8, respectively. In each figure, an axis of abscissa indicates timeand the axis of ordinate indicates the image velocity on the filmsurface. Accordingly, the area shown in the XY plane shows a distance,or blurring amount and so fourth.

In FIG. 9A, as described in step #930 of FIG. 8, Ubx≧UB_(K),T_(EV)<T_(K). In FIGS. 9A-9C, the blurring correction limitation speedis expressed using the image speed Fbx on the film surface and so forthbut not using a moving speed Ubx of a correcting lens LC and so forth asin FIG. 8. However, since a proportional relationship exists betweenthem as known from the relationship shown in FIG. 7, it is describedusing the image speed FBx on the film surface in FIGS. 9A-9C.

In FIG. 9A, as described above, the image speed Fbx on the film surfaceexceeds the correctable image speed |FBX| on the film surface, so that|Fbx|−FB_(K) corresponds to a blurring amount for a unit time. Bymultiplying the same by the exposure time T_(EV), that is, by theportion shown by the oblique lines in FIG. 9A, the blurring amount isexpressed. Here, the camera-shake amount detected by the angularvelocity sensor |Bx| is assumed to be constant.

FIG. 9B shows a case in which the image speed Fbx on the film surfaceexceeds the correctable speed FB_(K) of the image on the film surface,and also the exposure time T_(EV) exceeds the time usable for correctionT_(K). As in the case of FIG. 9A, the portion designated by obliquelines indicates the blurring amount which cannot be corrected.Accordingly, the blurring amount in this case can be obtained by adding(|Fbx|−FB_(K))·T_(K) and a value obtained by multiplying time whichbecome unusable for correction (T_(EV)−T_(K)) and a blurring amount fora unit time Fbx, that is, |Fbx|·(T_(EV)−T_(K)).

FIG. 9C shows a case where the image speed Fbx on the film surface issmaller than the correctable limit speed FB_(K), so that blurringtracking is possible concerning the image speed on the film surface, butthe exposure time T_(EV) exceeds the time usable for correction T_(K).In this case, the margin amount in the image speed on the film surface,or the margin amount for blurring expressed as (FB_(K)−|Fbx|)·T_(K)compensates for a part of the blurring amount on the exposure time side.

As described above, a blurring amount impossible to be corrected iscalculated. The blurring amount is obtained as Blx in steps #295, #305,#315 and #320 of FIG. 6. In FIG. 6, the steps #285 through #320 are thesame as the steps #910 through #930 of FIG. 8, so that the descriptionthereof is not repeated. After those values are found out, the programadvances to step #330, and a determination is made as to whether theabove obtained uncorrectable blurring amount Blx exceeds the permittableblurring amount BL_(K) (blurring, but of an amount permittable on apicture) or not. If the uncorrectable blurring amount Blx exceeds thepermittable blurring amount BL_(K), a flag BLxF is set and the programadvances to step #345. On the other hand, if the value is thepermittable blurring amount PL_(K) or less, the program directlyadvances to step #345 (#330-#340).

In the following steps #345-#415, the blurring amount in the y directionBLy is obtained in the same manner as that in the x directions Blx asdescribed above, so that the description thereof is not repeated.

Next, in step #420, absolute values of shake amount detected by angularvelocity sensors in the x direction and the y direction are compared inmagnitude. Such a comparison is made because it is sufficient to takelarger one in x or y direction as a blurring amount. Accordingly, insteps #440-#450, determining that the blurring amount in the y directionis larger than the blurring amount in the x direction, the blurringamount BLy in the y direction is inserted as the blurring amount BL. Onthe other hand, in steps #425-#435, determining that the blurring amountBx in the x direction is larger than the blurring amount By in the ydirection, the blurring amount Blx in the x direction is inserted as theblurring amount BL, and the program returns.

FIG. 10 shows a subroutine of display shown in step #205 of FIG. 4.Referring to FIG. 10, if either one of flags Blxf, BLyF showing that ablurring amount in the x or y direction is larger, blurring warning ismade, and if non of them is set, without making blurring warning, theprogram returns (#430-#445).

Next, referring to FIG. 8 again, process in the cases I-III shown inFIGS. 9A-9C where blurring correction tracking is impossible will bedescribed. Also, in such cases, some approach must be applied to reduceblurring amounts. In this invention, exposure time is reduced in orderto reduce blurring amount in such cases (#945). That is to say, as shownin FIG. 9A, for example, the area designated by the oblique line portioncorresponds to a blurring amount. In order to reduce the blurringamount, the area of the oblique line portion must be reduced. Theblurring amount cannot be corrected, however, by reducing the magnitudeof Fbx−FB_(K) by increasing the image speed FB_(K) on the film surface.This is because FB_(K) is a limitation image speed on the film surface.

Accordingly, in order to reduce the area of the oblique line portion,the exposure time T_(EV) should be moved toward the left side. That is,reducing an exposure time reduces a blurring amount.

Just reducing exposure time, however, cannot implement sufficientexposure amount. Accordingly, in the present invention, flash lightemission is used to compensate for the reduced portion of exposure timewhen reducing exposure time (#950). After that, photographing isperformed according to a normal routine (#935).

Next, a flow of exposure control according to the idea of reducingexposure time in order to reduce blurring amount as described above willbe described referring to FIGS. 11A-11C. First, in exposure control, AFcontrol is applied (#500). After completion of the AF control, blurringamount calculation is performed (#505, #510). Blurring amountcalculation (input of shake data ΔVx, ΔVy) is performed after completionof AF because of the following reasons. That is, when a lens is beingdriven, vibration of a motor and vibration by driving mechanism isproduced. It becomes camera-shake amount (angular velocity). If blurringcorrection is performed based on data which is not caused bycamera-shake actually produced by operation of a photographer, wrongcorrection is performed in exposure.

Next, a determination is made as to whether flags showing that therespective blurring amounts are large in the x and y directions are setor not, and when none of them is set, the program proceeds to step #570(#515, #520). If either one of flags Blxf and Blyf is set, the programproceeds to step #525, to calculate exposure time TA. The exposure timeTA corresponds to the exposure time reduced to reduce a blurring amountas described above, which is obtained by dividing the blurring amountexceeding the permittable amount PL_(K) by the angular velocity at thattime (a blurring amount for a unit time).

Next, a flow chart for calculating exposure time TA for reducing theblurring amount will be described referring to FIG. 12. First, it isdetermined whether the image speed |FB| on the film surface is not lessthan the predetermined limit speed FB_(K) on the film surface or not(#526). If |FB|<FB_(K) in step #526, the exposure time TA is found bysubtracting permittable value BL_(K) from an absolute value of theblurring amount (at this time exposure time T_(EV)>time usable forcorrection T_(K), and |FB|·(T_(EV)−T_(K)) is blurring amount BL) anddividing the same by an image blurring amount |FB| (#535).

When the image speed |FB| on the film surface is not less than the limitspeed FB_(K) on the film surface in step #526, a determination is madeabout T_(EV)≧T_(K). If, T_(EV)<T_(K), an exposure time TA for reducing ablurring amount is found out by dividing (|BL|−BL_(K)) obtained bysubtracting a permittable value BL_(K) from a blurring amount |BL|, by avalue (|FB|−FB_(K)) obtained by subtracting a correctable speed FB_(K)from an image blurring amount |FB| (#527, #537). If T_(EV)≧T_(K) in step#527, a determination is made as to whether the blurring amount on theimage surface {|BL|−|FB|·(T_(EV)−T_(K))} has already exceeded thepermittable value BL_(K) or not until exposure time T_(K) (#530). If itis determined that it exceeds the permittable value BL_(K) in step #530,the exposure should be finished before the exposure time T_(K), and theexposure time TA is obtained by adding the time at which the blurringtime until the exposure time T_(K) {|BL|−BL_(K)−|FB|·(T_(EV)−T_(K))}attains the permittable value and the time T_(K)−T_(EV) together. On theother hand, if {|BL|−|FB|·(T_(EV)−T_(K))}≦BL_(K) in step #530, a part ofthe blur amount between T_(K)−T_(EV) should be cut, the exposure time TAis obtained by TA=(|BL|−BL_(K))/|FB| from |BL|−|FB|·TA=BL_(K), and theprogram returns after processing of step #538 or #532.

Returning to FIG. 11A, after calculating TA in step #525, as statedabove, in order to reduce a blurring amount as much as possible, theexposure is set rather under a flash light is emitted to compensate forthe insufficient exposure amount. Flag FLF showing this is set in step#540. An exposure correction amount ΔEv is obtained from exposure timeT_(EV) and TA. this is because if an exposure time T_(EV) (Ev isobtained) is obtained, if the exposure time TA is found out from therelative relationship between the values, an exposure correction amountΔE_(V) is automatically found (#540, #545). A determination is made asto if the exposure correction amount ΔE_(V) is 2E_(V) or more or not instep #550. If ΔE_(V) is 2E_(V) or more, in consideration of a latitudeof film, ΔE_(V) is equal to 2, and if ΔE_(V) is less than 2E_(V) in step#550, it advances to step #560. The exposure value E_(V) is determinedto be E_(V)=E_(V)+ΔE_(V), and an aperture value A_(VD) when emittingflash light for obtaining a corrected exposure amount is calculated onthe basis of the correction value and the program advances to step #570(#560-#565). Although there is provided a limit of 2 in a value ofΔE_(V), it is desired to make a determination in step #550 with alatitude instead of 2 if the latitude can be read from a film container.

Next, the program advances to an aperture value calculating subroutine(#565), which contents will be described referring to FIG. 13. In theaperture value calculating subroutine, an aperture value A_(VD) is firstobtained with I_(V) (emission amount)+SV (film sensitivity)−D_(V)(distance)−ΔE_(V) (#805). Then, from the obtained exposure amount E_(V),an aperture value at that time (since a camera to which the presentinvention is applied is of a shutter and aperture in one system, anaperture value can be obtained in a one-to-one manner from an exposurevalue as well as a shutter speed) is obtained. The aperture value AV andthe aperture value A_(VD) at flash light emission obtained as describedare compared in magnitude (#810, #815). If AV>A_(VD) in step #815, thecontrol aperture value A_(VC) is AV, and if AV≦A_(VD), the controlaperture value A_(VC) is A_(VD). Thus, the aperture values are madesmall respectively and the program returns (#815-#825). Referring toFIG. 11B, the flow after step #570 will be described. Correction data Bxand By are supplied to a correction circuit Cxy, and an exposure timeT_(EV) is obtained again from the obtained exposure value E_(V) (#570,#575). In the repeated flow from exposure starting, a variable LTEshowing an exposure elapsed time until the previous time is reset, avariable ΔBL₁ of the blurring amount in the previous time is made 0, anexposure time T_(EV) is supplied as an output to an exposure controlcircuit AE, and next an exposure starting signal is supplied as anoutput to the exposure control circuit AE (#570-#590). Thus, theexposure control mechanism operates and a shutter is driven. next, ablurring amount is calculated again, correction data Bx and By aresupplied as outputs, and blurring amount correction is performed even ina release time lag period. (#595, #600). Then, starting of exposure on afilm surface is detected by switching on of a switch SST, when itattains ON, timer T_(E) showing exposure elapsed time is started,blurring amount is calculated for blurring correction again, and thecorrection data Bx and By are supplied as outputs (#615, #620). Fromstep #615, depending on the exposure time T_(EV), when the T_(EV) islong, blurring amount is calculated a plurality of times. To obtain timeΔT_(E) for performing the flow once from the previous time to this time,ΔT_(E) is found by T_(E)−LT_(E). An exposure time T_(E) at this time isregarded as LT_(E) (#625, #630). The uncorrected blur amount ΔBLproduced in the time ΔT_(E) due to change in the blurring speed isobtained as ΔT_(E)×(FB−FLB)·½. Adding the blurring amount until theprevious time and the blurring amount ΔBL at the present time together,a new value ΔBL₁ is obtained (#650, #655). It is multiplied by ½ asΔBL=ΔT_(E)×(FB−FLB)·½ because, assuming that the change in speedgradually occurs, the blurring amount produced at that time iscalculated. Next, obtaining a remaining time until completion ofexposure T₂ by T_(EV)−T_(E), a blurring amount produced in the time(uncorrectable amount) is predicted (#660). First, a determination ismade as to whether the blurring speed FB on the film surface is thecorrectable maximum speed FB_(K) or more or not, and if FB≧FB_(K), adetermination is made as to whether the exposure time T_(EV) is the timeusable for correction T_(K) or more or not (#665, #670). If it is notT_(EV)≧T_(K) in step #670, it is determined that a blurring predictionamount ΔBL₂=(FB−FB_(K))×T₂ (#675). If T_(EV)≧T_(K) in step #670, ablurring prediction amount ΔBL₂=(FB−FB_(K))·T₂+FB·(T_(EV)−T_(K)) and theprogram proceeds to step #700. If FB<FB_(K) in step #665, T_(K) 1 isobtained from (FB_(K)−|FB|)·T_(K)/FB+T_(K), it is determined whetherT_(EV)≧T_(K1) or not (#667, #685). If T_(EV)≧T_(K1) in step #685, theblurring prediction amount ΔBL₂=FB·(T_(EV)−T_(K)), and if T_(EV)<T_(K1),the blurring amount ΔBL₂=0, and the program proceeds to step #700(#685-#695).

Next, an uncorrectable blurring region till that point |ΔBL₁| and apredicted blurring amount ΔBL₂ are added together to obtain ΔBL₃, and itis determined whether this is a permittable predetermined value BL_(K)or more or not (#700, #705). ΔBL₃ is obtained in this way in order toamend exposure correction when the predicted blurring amount and anactual blurring amount are different from each other, with exposurecorrection performed when the blurring amount is large. Then, ifΔBL₃≧BL_(K) in step #705, the program proceeds to step #710, and ifΔBL₃<ΔBL_(K), the program proceeds to step #795.

The flow after step #710 will be described referring to FIG. 11C. IfΔBL₃≧BL_(K) in step #705, although control to reduce exposure timeshould be further performed, when the correction amount ΔE_(V) exceeds 2in step #710, no more correction is performed and the program proceedsto step #770. If ΔE_(V)<2 in step #710, a permittable predeterminedamount BL_(K) is subtracted from an actual blurring amount ΔBL₃ to findout the difference ΔB′L, which is divided by the blurring speed FB atthat time to obtain T_(A) (#715, #720). Then, an exposure correctionamount ΔE_(V) 2 is obtained from an exposure time T_(EV) and TA, and adetermination is made as to whether the amount obtained by adding anexposure correction amount ΔE_(V) till then and the above ΔE_(V) 2 is 2or more or not (#730) If it is 2 or more in step #730, determiningΔE_(V) 2=2−ΔE_(V) (#735), if it is less than 2, the program skips step#735 and the program proceeds to step #740, respectively (#735).

In step #740, E_(V)=E_(V)+ΔE_(V) 2, an exposure time T_(EV) isre-obtained from this, and then T_(EV)=T_(EV)−T₂, and T_(EV) isoutputted (#740-#755). A flag FLF indicating flush light emission isset, an aperture value A_(VD) is calculated, and the program proceeds tostep #770. In step #770, a determination is made as to whether a shutterclosing signal is supplied as an output from exposure control circuit AE(shutter closing operation has already been performed) or not, if ashutter closing signal is not supplied, the program returns to step#615, and the flow after that point is performed. If a closing signal issupplied as an input, the program proceeds to step #775 to determine ifa flag FLF is set or not (#775). If flag FLF is set in step #775, anabsolute aperture value AV is supplied, AV≧A_(VC) or not is determined,and if AV<A_(VC), the program returns to step #780 (#780-#785). On theother hand, when AV≧A_(VC) in step #785, a flush light emission signal(terminal EMI) is outputted to flush circuit FL to apply flush lightemission and the program returns (#785, #790). When the flag FLF is notset in step #775, the program immediately returns.

If ΔBL₃<BL_(K) in step #705, the program proceeds to step #795 (FIG.11C), a determination is first made as to whether the correctionexposure amount ΔE_(V) is 0 or not, and if it is 0, the program proceedsto step #770 (#795). If ΔE_(V) is not 0 in step #795, a permittablecorrection amount BL_(K) is subtracted from the blurring amount ΔBL₃,dividing the same by the blurring speed FB at that time to obtain anexposure time TA (#775-#805). Next, an exposure correction amount ΔE_(V)2 (>0) is obtained from exposure times T_(EV), TA (#810). Next,comparing the exposure correction amount ΔE_(V) until the previous timeand the above ΔE_(V) 2, if ΔE_(V)≧ΔE_(V) 2, the program proceeds to step#830. If ΔE_(V)<ΔE_(V) 2 in step #815, to make an exposure correctionamount 0, it is determined ΔE_(V)→ΔE_(V) 2, the flush light emissionflag FLF is reset, and the program proceeds to step #830 (#815-#825).And then, with ΔE_(V)=−ΔE_(V) 2, the program proceeds to step #740(#830).

FIGS. 14A and 14B are diagrams showing the relationship betweenopening/closing of a shutter and time. FIG. 14A is a diagram showing acase of normal blurring correction, and FIG. 14B is a diagram showingthe conditions which the present invention is applied to. In eachfigure, the area in the portion designated by a trapezoid shows anappropriate exposure amount in the case where normal light is employed.Referring to FIG. 14A, when a normal blurring correction is applied, intime from the point M at which the blurring correction is detected to beimpossible and to the point of shutter closing, or in the regiondesignated by OVB, the blurring correction could not finnish. As aresult, blurring is produced.

Referring to FIG. 14B, when blurring correction according to the presentinvention is performed, an exposure amount is re-calculated at the pointM at which it is detected that blurring correction is impossible, anexposure time TA is obtained, and it shifts to the control for emittingflush light if needed. Here, the control is performed flushmatically. Asshown in the figure, the aperture is started to be closed, flush isemitted at the point denoted with N to reduce a blurring amount.

By the control, as compared to the case where flush is emitted from thefirst point, according to the present invention, a normal light isutilized as much as possible, so that solid and excellent pictures couldbe taken.

Returning to FIG. 3, if a preparatory switch S1 is OFF in step #25, adetermination is made as to whether charging is completed or not, andwhen the charging is completed, boosting is stopped. In step #40, adetermination is made as to whether a power source holding timer T₁ hascounted 10 seconds or not. If the timer T₁ has not counted 10 seconds,the program shifts to step #30 to carry out a determination of S1 ON. Ifthe timer T₁ has counted 10 seconds in step #40, a feeding transistorTr1 is turned off in step #45 to stop supplying power to the firstperipheral circuit CT₁ including light measuring circuit LM and soforth. In step #50, feeding transistor Tr2 is turned off, power supplyto the second peripheral circuit CT₂ including angular velocity sensorsSx, Sy is stopped, and the display by the display circuit DISP istotally eliminated in step #55. Then, a flag S1 OFF indicating that thepreparatory switch S1 is OFF is set in step #60, and the programperforms the flow from #10.

Although the present invention has been described and illustrated indetail, it is clearly understood that the same is by way of illustrationand example only and is not to be taken by way of limitation, the spiritand scope of the present invention being limited only by the terms ofthe appended claims.

What is claimed is:
 1. A camera capable of correcting fluttering of anobject image due to camera-shake, comprising: camera-shake detectingsensor for detecting said camera-shake and for outputting camera-shakeinformation; taking lens for forming said object image; correcting meansfor shifting a position of the object image based on the camera-shakeinformation such that the object image remains stationary during anexposure; driving means for driving an optical member in said takinglens; and control means for controlling said correcting means so thatsaid correcting means does not use an output of said camera-shakedetecting sensor when said optical member is being driven.
 2. The cameraaccording to claim 1, wherein said optical member is a focusing lensused for focusing said object image onto a predetermined focal point. 3.The camera according to claim 1, wherein said camera-shake detectingsensor comprises an acceleration sensor.
 4. A camera capable ofcorrecting fluttering of an object image due to camera-shake,comprising: a camera-shake detecting sensor for detecting saidcamera-shake and for outputting camera-shake information; correctingmeans for shifting a position of the object image based on thecamera-shake information such that the object image remains stationaryduring an exposure; an actuator for performing predetermined operationfor photographing; motor driving means for driving said actuator; andcontrolling means for forbidding fluttering correction based oncamera-shake information obtained during operation of said drivingmeans.
 5. The camera according to claim 4, wherein said camera-shakedetecting sensor comprises an acceleration sensor.
 6. The cameraaccording to claim 5, further comprising: a focus adjusting opticalsystem used for focusing said object image onto a predetermined focalpoint; and said actuator driving said focus adjusting optical system. 7.A camera capable of correcting fluctuation of an object image due tocamera-shake, comprising: a power source; boosting means for boostingsaid power source voltage; charge means to be charged with said boostedvoltage; flash means applied with power from said charge means foremitting flashlight; a sensor supplied with power by said power sourcefor detecting a camera-shake; correcting means for correctingfluctuation of the object image due to said camera-shake according tothe output of said sensor such that the object image remains stationaryduring an exposure; and controlling means for controlling saidcorrecting means so that correction on the basis of said sensor outputprovided during operation of said boosting means is not performed.
 8. Acamera capable of correcting image movement due to camera-shake,comprising: exposure amount controlling means for controlling exposureto film; camera-shake detecting sensor for detecting said camera-shake;correcting means for correcting movement of the object image based onthe output of said camera-shake detecting sensor; determining means fordetermining whether the movement can be properly corrected or not;auxiliary light means for lightening said object; and controlling meansfor making said auxiliary light means emit light when said determiningmeans determines that said movement cannot be properly corrected inexposure.
 9. A camera according to claim 8, wherein said determiningmeans comprises a velocity calculating means for calculating velocity ofthe object image on the basis of said sensor outputs and determineswhether said correction is correctly performed or not on the basis ofsaid velocity.
 10. A camera according to claim 8, further comprising:exposure time setting means for setting exposure time; and saiddetermining means determining whether said correction is correctlyperformed or not on the basis of said exposure time.
 11. A cameraaccording to claim 8, further comprising: exposure time setting meansfor setting exposure time, and wherein said controlling means changesaid exposure time set by said exposure time setting means into anexposure time shorter than said set exposure time and also makes saidauxiliary light means emit light when said determining means determinesthat said movement cannot be properly corrected in said exposure.
 12. Acamera capable of correcting an object image due to camera-shake,comprising: a power source; a circuit consuming a large amount of powerduring operation, the voltage of said power source fluctuating due tothe consumption; a sensor supplied with power by said power source fordetecting a camera-shake; and correcting means for correcting movementof an object image due to said camera-shake according to the output ofsaid sensor and not to correct on the basis of said sensor output thatis provided during operation of said circuit.
 13. A camera according toclaim 12, wherein said circuit comprises boosting means.
 14. Kindlycancel claim 14 without prejudice or disclaimer.
 15. A cameracomprising: (a) exposure amount controlling means for controllingexposure of film; (b) camera-shake detecting sensor for detectingcamera-shake amount during exposure operation; (c) determining means fordetermining whether amount of fluctuation of an object image due to thecamera-shake exceeds a predetermined value or not based on saidcamera-shake amount; (d) auxiliary light means for lighting said object;and (e) control means for controlling said auxiliary light means basedon the result determined by said determining means.
 16. The cameraaccording to claim 15, said camera further comprising: (f) exposureterminating means for terminating said exposure operation of saidexposure amount controlling means when said determining means determinesthat said amount of fluctuation exceeds said predetermined value.
 17. Acamera according to claim 16, wherein said control means controls saidauxiliary light means to emit light when difference of exposure amountupon termination of exposure by said exposure terminating means from apredetermined exposure amount exceeds a predetermined value.
 18. Acamera according to claim 16, wherein said control means controls saidauxiliary light means to emit light by amount corresponding to thedifference between the exposure amount when the exposure is terminatedby said exposure terminating means and a prescribed exposure amount. 19.A camera comprising: (a) exposure amount controlling means forcontrolling exposure to film; (b) camera-shake detecting sensor fordetecting said camera-shake amount during exposure operation; (c)determining means for determining whether amount of fluctuation of anobject image exceeds a predetermined value or not based on saidcamera-shake amount; and (d) control means for terminating exposureoperation of said exposure amount controlling means when saiddetermining means determines that the fluctuation amount exceeds apredetermined value.
 20. A camera according to claim 19, furthercomprising: (e) auxiliary light means for lighting said object; andwherein said control means controls said auxiliary light means to emitlight when difference of exposure amount upon termination of exposure bysaid exposure terminating means from a predetermined exposure amountexceeds a predetermined value.
 21. The camera according to claim 19,further comprising: (f) auxiliary light means for lighting said object;and wherein said control means controls said auxiliary light means toemit light by amount corresponding to the difference between exposureamount when the exposure is terminated by said control means and aprescribed exposure amount.
 22. A camera capable of detecting flutteringof an object image due to camera-shake, comprising: a camera-shakedetecting sensor for detecting camera-shake and for outputtingcamera-shake information; a taking lens for forming said object image; adriving device for driving an optical member in said taking lens; and acontrol device for controlling a predetermined operation of the camerabased on the camera-shake information, wherein said control device doesnot use the camera-shake information when said optical member is beingdriven.
 23. The camera according to claim 22, wherein said controldevice includes a correcting device for shifting a position of theobject image based on the camera-shake information such that the objectimage remains stationary during an exposure, and does not use thecamera-shake information for correcting the position of the object imagewhen said optical member is being driven.
 24. The camera according toclaim 23, wherein said correcting device uses the camera-shakeinformation after the driving of the optical member has been completed.25. The camera according to claim 22, wherein said optical member is afocusing lens used for focusing said object image onto a predeterminedfocal point.
 26. The camera according to claim 22, wherein saidcamera-shake detecting sensor includes an angular velocity sensor.
 27. Acamera capable of detecting fluttering of an object image due tocamera-shake, comprising: a camera-shake detecting sensor for detectingsaid camera-shake and for outputting camera-shake information; anactuator for performing a first predetermined operation forphotographing; a motor driving device for driving said actuator; acontrol device for controlling a second predetermined operation forphotographing, which is different from said first predeterminedoperation, based on the camera-shake information; and an inhibitingdevice for inhibiting control of said second predetermined operationbased on camera-shake information that is obtained while said actuatoris being driven by said driving device.
 28. The camera according toclaim 27, wherein said control device includes a correcting device forshifting a position of the object image based on the camera-shakeinformation such that the object image remains stationary during anexposure, and said inhibiting device inhibits fluttering correctionbased on camera-shake information that is obtained while said actuatoris being driven.
 29. The camera according to claim 27, furthercomprising: a focus adjusting optical system used for focusing saidobject image onto a predetermined focal point; and wherein said actuatordrives said focus adjusting optical system.
 30. The camera according toclaim 27, wherein said camera-shake detecting sensor includes an angularvelocity sensor.
 31. A camera capable of detecting fluctuation of anobject image due to camera-shake, comprising: a power source; a boostingdevice for boosting said power source voltage; a charge device to becharged with said boosted voltage; a flash device applied with powerfrom said charge device for emitting flash light; a sensor supplied withpower from said charge device for detecting camera-shake; and a controldevice for controlling a predetermined operation of the camera based onan output of said sensor, wherein said control device does not use theoutput of said sensor when said boosting device is boosting said powersource voltage.
 32. The camera according to claim 31, wherein saidcontrol device includes a correcting device for correcting fluctuationof the object image due to said camera-shake based on the output of saidsensor such that the object image remains stationary during an exposure,and does not use the output of said sensor for the fluctuationcorrecting when said boosting device is boosting said power sourcevoltage.
 33. The camera according to claim 31, wherein said controldevice includes a display device for display information based on theoutput of said sensor, and does not use the output of said sensor forthe displaying operation when said boosting device is boosting saidpower source voltage.
 34. The camera according to claim 31, wherein saidsensor includes an angular velocity sensor.
 35. A camera capable ofdetecting movement of an object image due to camera-shake, comprising: apower source; a circuit consuming a large amount of power duringoperation, the voltage of said power source fluctuating due to theconsumption; a sensor supplied with power by said power source fordetecting camera-shake; and a control device for controlling apredetermined operation of the camera based on the output of saidsensor, wherein said control device does not use the output of saidsensor when said circuit is operating.
 36. The camera according to claim35, wherein said control device includes a correcting device forcorrecting movement of the object image due to said camera-shake basedon the output of said sensor such that the object image remainsstationary during an exposure, and does not use the output of saidsensor for the movement correcting when said circuit is operating. 37.The camera according to claim 35, wherein said circuit includes boostingdevice.
 38. A camera capable of detecting fluctuation of an object imagedue to camera-shake, comprising: a power source; a boosting device forboosting said power source voltage; a charge device to be charged withsaid boosted voltage; a flash device applied with power from said chargedevice for emitting flash light; a detecting device supplied with powerfrom said charge device for detecting camera-shake; and a control devicefor controlling said boosting device and detecting device so that aboosting operation and a detecting operation are not conducted at thesame time.
 39. The camera according to claim 38, further comprising: adisplay device for displaying information based on the output of saiddetecting device, wherein said control device controls said boostingdevice and display device so that a boosting operation and a displayingoperation are not conducted at the same time.
 40. The camera accordingto claim 38, further comprising: a charge complete detecting device fordetecting that said charge device is charged to a predetermined level,wherein said control device controls said camera-shake detecting deviceso as to detect camera-shake after the charging operation is completed.41. A camera capable of correcting movement of an object image due tocamera-shake, comprising: a first operating member which is to beoperated by a user; a detecting device, which works in response to anoperation of said first operating member, for detecting camera-shake; adisplay device, which works in response to the operation of said firstoperating member, for displaying information based on the detectedcamera-shake; a second operating member which is to be operatedsuccessively after said first operating member by the user; an exposurecontrol device, which works in response to the operation of said secondoperating member, for controlling an exposure for photographing; and acorrecting device, which works in response to the operating of saidsecond operating member, for correcting movement of the object image dueto said camera-shake based on the detected camera-shake such that theobject image remains stationary during an exposure.
 42. The cameraaccording to claim 41, wherein said first operating member is a switchwhich is turned on by a half depression of a release button of thecamera, and said second operating member is a switch which is turned onby a complete depression of the release button.
 43. A camera capable ofdetecting movement of an object image due to camera-shake, comprising: amanual operating member which is to be operated by a user; a distancemeasuring device for measuring a distance to the object; a detectingdevice for detecting camera-shake; a first control device forcontrolling said distance measuring device so as to start the distancemeasurement in response to the operation of said manual operating memberand to conduct the distance measurement only once during the operationof said manual operating member; and a second control device forcontrolling said detecting device so as to start the camera-shakedetection in response to the operation of said manual operating memberand to repeat the camera-shake detection during the operation of saidmanual operating member.
 44. The camera according to claim 43, furthercomprising: a light measuring device for measuring brightness of theobject; and a third control device for controlling said light measuringdevice so as to start the light measurement in response to the operationof said manual operating member and to conduct the light measurementonly once during the operation of said manual operating member.
 45. Thecamera according to claim 43, wherein said manual operating member is aswitch which is turned on by a half depression of a release button ofthe camera.
 46. The camera according to claim 43, further comprising: alens shutter which works not only as a shutter but as an aperture stop.47. A camera capable of correcting image blur due to camera-shake,comprising: a camera-shake sensor which detects camera-shake; an opticalsystem which is driven to correct image blur in accordance with saidcamera-shake detected by said camera-shake sensor; a determination meansfor determining whether or not said optical system is movable at a speednecessary to correct the image blur during an exposure operation; anexposure control which reduces exposure time when the determinationmeans determines said optical system is not movable at said speed; and acompensating control which compensates the reduced exposure time. 48.The camera as claimed in claim 47 further comprising an auxiliary lightwhich illuminates an object image, wherein said compensating controlenergizes said auxiliary light to compensate the reduced exposure timewhen the exposure control reduces the exposure time.
 49. The camera asclaimed in claim 47 wherein said optical system is driven at the speednecessary for correcting the image blur when the determination meansdetermines the optical system is movable.
 50. A camera capable ofcorrecting image blur due to camera-shake, comprising: a camera-shakesensor which detects camera-shake; a determination means for determiningduring exposure whether or not said camera-shake detected by saidcamera-shake sensor can be properly corrected; an exposure control whichreduces exposure time when the determination means determines saidcamera-shake detected by said camera-shake sensor can not be properlycorrected; and a compensating control which compensates the reducedexposure time.
 51. The camera as claimed in claim 50 further comprisingan auxiliary light which illuminates an object image, wherein saidcompensating control energizes said auxiliary light to compensate thereduced exposure time when the exposure control means reduces theexposure time.
 52. An image blur correcting method used in a camera,comprising the steps of: detecting camera-shake; determining duringexposure whether or not said detected camera-shake can be properlycorrected; reducing exposure time when the determination of saiddetermining step is negative; and compensating the reduced exposuretime.
 53. The image blur correcting method as claimed in claim 52further comprising the step of driving an optical system for correctingthe image blur in accordance with said detected camera-shake.
 54. Theimage blur correcting method as claimed in claim 52 wherein saidcompensating step includes the step of illuminating an object with anauxiliary light when the exposure time is reduced in said reducing step.